1. Field of the Invention
The present invention relates to a pipe connector adapted for use in releasably connecting a high-pressure fluid pipe.
2. Description of the Related Art
Various pipe connectors have conventionally been used to connect a vessel filled with a high-pressure fluid to another vessel or a pipe or to connect high-pressure fluid pipes to one another, for example. The basic construction of these pipe connectors is generally known. In the connector of a type in which a normally-closed valve is provided only on the socket side, a socket on the fluid-supply side and a plug on the pipe side are connected by pushing the valve open by means of the distal end of the plug to cause the respective flow passages of the socket and the plug to communicate with each other, so that the high-pressure fluid is introduced into the pipe for transportation.
In the socket through which the high-pressure fluid flows, however, the pressure of the fluid acts on the rear face of the valve body of the normally-closed valve, and also on the distal end face of the plug. In connecting the socket and the plug, therefore, these elements are subjected to a substantial thrust load. Accordingly, the socket and the plug can be connected only with use of a force great enough to resist the thrust load. If the outside diameter of the plug and the pressure of the high-pressure fluid are 6 mm and 70 kgf/cm.sup.2, respectively, a force of approximately 19.79 kgf acts on the front end face portion of the plug, and also on the valve. It is not very easy for an operator, therefore, to push the plug into the socket so that the valve body is fully retreated against the pressure of the fluid.
Thus, according to the conventional high-pressure fluid connector, connecting the socket and the plug requires a great force, and sometimes cannot be accomplished by human strength. If the valve is opened without satisfactory connection, moreover, the fluid may unexpectedly rush out from the gap between the socket and the plug, thus involving a serious risk and lowering the operating efficiency. If the high-pressure fluid is discharged into the open air during the connecting operation, then it entails an unnecessary waste, as well as danger. Depending on the kind of the fluid handled, this problem may possibly develop into an issue of environmental pollution.